[MLton] MLton HOL
Stephen Weeks
MLton@mlton.org
Thu, 1 Jul 2004 07:36:47 -0700
> Unfortunately debugging the MLton HOL programs is hard, and I'm often
> reduced to feeding in prefixes of the program to see if they produce
> the same error :-(
Are you aware of "-exn-history true"? This might help, since the top
level handler will at least then display where the exception was
raised.
> The exception HOL_ERR contains useful debugging information, but
> since I don't know where it's being raise I can't wrap the correct
> function in an exception handler.
>
> I don't suppose it would be possible for ask MLton to print more than
> just "unhandled exception: x"?
This gives me an idea for a pretty easy improvement to MLton. We
could add
val MLton.Exn.addTopLevelPrinter: (exn -> string option) -> unit
This would let you add your own exn pretty printers to the top level
handler.